Safety gas valve



J. P. ISAACS SAFETY GAS VALVE Dec. 8, 1936.I

Filed March 2, 1936 1 l I I z I I m l W l l m, o

ATTOR N EY Patented Dec. 8, 1936 PATENT OFFICE SAFETY GAS VALVE Jasper P. Isaacs, Shan'n'ook, Tex., assignor of one-half to John Porter, Shamrock, Tex.

Application March 2, 1936, Serial No. 66,744

1 Claim.

This invention relates to safety gas valves especially adapted for gas supply lines between the latter and stoves or similar devices and has for the primary object, the provision of means which will automatically close the supply line to the stove when the pressure of the gas falls below a predetermined amount or to a pressure which would cause extinguishing of the fiame of the stove so that on the return of the gas pressure to normal, the gas will be prevented from escaping at the stove.

With these and other objects in view this invention consists in certain novel features of construction, combination and arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had to the following description and accornpanying drawing, in which Figure l is a side elevation illustrating a safety gas valve constructed in accordance With my invention.

Figure 2 is an endvelevation illustrating the same.

Figure 3 is a sectional View taken on the line 3-3 of Figure 2, showing the valve in a closed position to stop the flow of gas therethrough.

Figure 4 is a view similar to Figure 3, showing the valve positioned to permit passage of gas therethrough.

Referring in detail to the drawing, the numeral l indicates a casing having inlet and outlet nipples 2 and 3. The inlet nipple 2 is connected to a gas supply line while 'the nipple t is connected to a line leading to a stove or similar device furnished with gas from the supply line. The inner end of the nipple 3 terminates into a cylinder i and one wall of the cylinder is provided with a port 5. The passage of the nipple where is communicates with the cylinder :i

is reduced to form a conical shaped seat t arranged adjacent to the port 5 and is adapted to Je engaged by a Weighted valve or plunger i pivotally connected to a link 8 which is in turn pivoted to one end of a bell crank lever 9. The lever 9 is pivoted in the casing and has pivoted to its other arm a link IO provided with a notch ll. The link 10 is pivoted to a lever 12 and the latter is pivotally connected to the casing, as

shown at lyand carries a Valve element I'i. The nipple 2 projects into the casing and forms a seat 45 to be engaged by the valve M. A dog is 'pivoted in the casing and engages the link Ill and is connected 'to a spring pressed finger 5 piece il' slidably supported by the casing Whereby a person may effect pivotal movement of the. dog. The dog when in engagement with the notch li looks the valve l'l against its respective seat and the plunger 'l in engagenient with its 10 seat, olosing the passage between the nipples 2 and 3. A pressure on the finger piece ll will disengage the dog from the notch. w

In operation, the normal pressure of the gas vthrough the casing `i is sufficient to maintain the 15 Valve i away from its seat and the plunger in an elevated position, as shown in Fgure 4. The valve and plunger, as shown in Fgure 4, permit a free passage of the gas through 'the casing. f-Iowever, should the pressure fall below a pre- 20 determined amount, the plunger 'i gravitates and closes the valve iii and the dog engages the notch li, preventing the valve Ill from again opening when the pressure of the gas increases or returns to normal. With the pressure of the gas 25 at normal and the valve iii locked in a seated position, the latter may be released by pressure applied to the finger piece H.

While I have lshown and described ,the preferred embodiment of my invention, it will be 30 understocd that minor changes in construction, combination and arrangement of parts may bemade without departing from the spirit and scope of my inventon, as claimed.

Having described the invention, I claim: 35

A safety gas valve comprising a casing, inlet andv outlet nipples for said casing, a valve seat on the inlet nipple, a cylinder formed in the outlet nipple and having a port in communication with the interior of the casing, a pivoted valve 40 in the casing to engage the seat, a plunger slidable in the cylinder, linkage between the plunger and valve and having a notch, a spring pressed dog pivoted in the casing to ride against the linkage and engage the notch when the valve is 45 in a seated position to prevent opening of said valve, and a finger piece for effecting movement of the dog.

' JASPER P. ISAACS. 

